This invention relates to folding constructions of metal or steel tubes, particularly to folding sport strollers etc., comprising at least one pair of folding angular supporting legs having supporting elements at their supporting ends, for instance wheels pivoted on wheel axles set up at right angles to said supporting legs, whereby the first supporting leg, for instance the back one, has an upward extension beyond the folding axle between the legs.
It is the fixation of the mutual position of the supporting legs, the stroller being ready to use, which is essential, since the question is to obtain a construction of low weight, easy to manufacture, to handle and to transport.
In a known construction the angular supporting legs have been linked together below their mutual pivot by means of a double link, which, when the angular supporting legs are unfolded, forms a continuous drag link, but which when the angular supporting legs are to be collapsed, is folded in half so that each of the link parts is folded together with the angular legs. Such a construction is very light and easy to manufacture, but in handling it requires both hands to be free in order to handle both the angular supporting legs and the fixing links as desired.
In another construction a trapezoid linkage is arranged above the bearing point of the angular supporting leg, which, the supporting legs being unfolded, are made to function as a triangle formed supporting construction by means of extra locking rings, but which, when the angular supporting legs are to be folded by pulling away the rings, return to a trapezoid linking system which is collapsed together with the angular supporting legs.
Even for handling this construction both hands must be free. Besides, such a construction is difficult to manufacture and to utilize and finally it is made heavy by the multiplicity of links.